Asymmetrically inclined rhombic antenna

ABSTRACT

AN ANTENNA ARRAY EMPLOYING ASYMMETRICALLY INCLINED &#34;RHOMBIC&#34; ANTENNA ELEMENTS IN WHICH THE SIDE LENGTH L1, SEMI-ACUTE ANGLE A1, AND INCLINE ANGLE T1 TO THE HORIZONTAL OF THE INPUT V SECTION DIFFERS FROM THE SIDE LENGTH LO, SEMI-ACUTE ANGLE AO, AND INCLINE ANGLE TO, OF THE OUTPUT OR TERMINATING V SECTION OF THE &#34;RHOMBIC&#34; ELEMENT.

1971 J. T. DE BETTENCOURT 3,564,550

4 ASYMMETRICALLY INCLINED RHOMBIC ANTENNA Filed March 29, 1967 INVENTOR JOSEPH z deBETTEA/COURT BYM s,

A ram Er United States Patent Office 3,564,550 Patented Feb. 16, 1971 US. Cl. 343-733 2 Claims ABSTRACT OF THE DISCLOSURE An antenna array employing asymmetrically inclined rhombic antenna elements in which the side length L semi-acute angle A,, and incline angle T to the horizontal of the input V section differs from the side length L semi-acute angle A and incline angle T of the output or terminating V section of the rhombic element.

BACKGROUND OF THE INVENTION The properties of horizontal rhombic antennas are well known. The plane of the rhombic may be inclined at some incline angle T measured with respect to the horizontal. Such systems have been used for high frequency communication and backscatter applications. However, presently known rhombic antennas are limited in their gain and in beam pattern capabilities.

An object of the present invention is to provide an improved rhombic antenna.

Another object of the present invention is to provide an asymmetrically inclined rhombic antenna array. Yet another object of the present invention is to provide an asymmetrically inclined rhombic antenna which provides a multi-beam directivity for transmission or reception.

Another object of the present invention is to provide an asymmetrically inclined rhombic antenna which may be used for improving HF /VHF communications by improved wideband antennas with single or multiple beams.

An advantage of one form of asymmetrically inclined rhombic antenna known as a humped-back rhombic antenna is that only the mid-poles are of the greatest height and there are associated advantages in gain and beam pattern. Another advantage of asymmetrically sloped rhombics is that they may be arrayed in end-fire to provide lower side lobes and greater gain than is obtainable with the symmetrical sloped rhombic. Asymmetrically sloped rhombics may also be arranged to beam along different azimuths and elevations, the long axes being rotated about the mid-pole positions.

SUMMARY OF THE INVENTION The above objects and advantages of the present invention are achieved by providing an antenna array comprising asymmetrically inclined rhombic antenna elements.

More specifically, the above objects and advantages of the present invention are achieved by providing an antenna array having an input V section including a pair of antenna elements having side length L acute angle A, between the antenna elements and axis of the input V section and an incline angle T to the horizontal of the plane of the input V section; and an output V section including a pair of antenna elements having side length L acute angle A between the antenna elements and the axis of the output V section and an incline angle T to the horizontal of the plane of the output V section.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side view of an asymmetrical rhombic antenna of the present invention;

FIG. 2 is a top view of the antenna shown in FIG. 1;

FIG. 3 is an isometric view of the antenna shown in FIGS. 1 and 2; and

FIG. 4 is an alternative embodiment of the invention shown in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. l-3 show an asymmetrically inclined rhombic antenna 10 embodying the present invention. Vertical mid-poles 12 with respect to the ground are provided to support the elements of the antenna 10. An input V Section 13 of the antenna 10 is provided, which may be fed by any conventional antenna feed such as that disclosed in Pat. No. 2,208,810 to M. Katzin and comprises antenna elements 14. The antenna elements 14 each have length L. The angle between the two elements 14 making up the input V section 13 of the antenna 10 is acute angle 2A while the angle between one of the elements 14 and the axis of the input V section 13 represented by dotted line 20 is another acute angle A. The angle of the plane of the elements 14 of the input V section 13 with respect to the horizontal is an angle T The dotted line 18 between the mid-poles 12 represents the cross-axis of the antenna.

The antenna 10 also includes an output V section 15 comprising antenna elements 16. The output V section 15 is connected to ground as shown at 17. The antenna elements 16 of the output V section 15 each have a length L which differs from the length L, of the antenna elements 14 of the input V section 13. The angle between the antenna elements 16 of the output V section 15 is an acute angle 2A while the angle between one of the elements 16 and the axis of the output V section 15 represented by dotted line 22 is another acute angle A The acute angle 2A of the input V section 13 differs from the acute angle 2A of the output V section 15. Finally, the angle between the plane of the antenna elements 16 and the horizontal is an angle T which differs from the incline angle T with respect to the horizontal of the plane of the antenna elements 14. Because the side length L and L the semi-acute angles A, and A between the antenna elements 14 and 16 respectively, and the incline angles T and T with respect to the horizontal of the antenna elements 14 and 16 respectively difier, the rhombic antenna 10 is considered to be an asymmetrically inclined rhombic antenna.

The embodiment of the invention shown in FIG. 4 differs from that shown in FIG. 3 only in that the output V section 15 made up of the antenna element 16 is supported entirely above and makes no contact with the ground. In all other respects, the embodiment of FIG. 4 has the exact same characteristics as that shown in FIG. 3.

In the present invention it T =T =0 degrees, the rhombic is then the usual horizontal rhombic of the prior art. If T =T =T, the rhombic is the well known inclined rhombic inclined at an angle T. In the present invention, however, since T differs from T the antenna is an asymmetrically inclined rhombic antenna. The angles T and T may either be positive or negative with respect to the horizontal. If T, is greater than 0 degrees and T is less than 0 degrees, then the antenna is known as a humped-back rhombic. This humped-back rhombic has an advantage in that only the mid-poles are of the greatest height and there are associated advantages in gain and beam pattern. Of further interest is the semisloped rhombic where T, is greater than 0 degrees and T is equal to 0 degrees. Asymmetrically sloped rhombics may be arrayed in end-fire to provide lower side lobes and greater gain as in the situation of the symmetrical case where T,=T =T. Asymmetrically sloped rhombic antennas may be arranged to beam along dilferent azimuths and elevations, the long axes being rotated about the mid-pole positions for example. These rhombics then may be combined to provide multi-beam directivity for transmission or reception. Asymmetrically inclined rhombic antenna arrays of the present invention may be used for improving HF/VHF communications by improved wideband antennas with single or multiple beams.

Obviously, many modifications and variations of the present invention are possible in the lightof the above teachings. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

I claim: 1. An asymmetrically inclined rhombic antenna comprising:

an input V section, said input V section including a pair of antenna elements formed in a V and having side length L an acute angle A between the pair of elements and the axis of the input V section and an incline angle T between the horizontal and the plane formed by the input V section; and an output V section electrically connected to said input V section, said output V section including a pair of antenna elements formed in a V and having side length L an acute angle A between the pair of elements and the axis of the input V section and an incline angle T between the horizontal and the plane formed by the input V section, said output V section lying in a plane parallel to the horizontal where the lengths L and L and the acute angles A and A are not equal to one another, the antenna being solely supported at the intersection of said input and output V sections. 2. An asymmetrically inclined rhombic antenna comprising:

an input V section, said input V section including a pair of antenna elements formed in a V and having a side length, an acute angle between the pair of elements and the axis of the input V section and an angle of incline between the horizontal and the plane formed by the input V section; and

an output V section electrically connected to said input V section, the apices of said input and output V sections lying in a common horizontal plane, said output V section including a pair of antenna elements formed in a V and having a side length, an acute angle between the pair of elements and the axis of the horizontal V section, and an angle of incline between the horizontal and the plane formed by the output V section, where the side lengths, the acute angles and the angles of incline of the input V and output V are configured unequal to one another, thereby providing increased beam control and directivity.

References Cited UNITED STATES PATENTS 2,076,222 4/1937 Bruce 343886 2,167,735 8/1939 Alford 343-731 2,208,810 7/1940 Katzin 343-733 2,700,733 1/1955 Brueckmann 343-733 919,115 4/1909 Babcock 343-886 FOREIGN PATENTS 924,152 3/1947 France 343-731 940,238 3/1956 Germany 343--734 ELI LIEBERMAN, Primary Examiner U.C. Cl. X.R. 

